Description

< pq> if I have a compositor running on DRM/KMS and EGL/GBM (yes, weston), is there any way I could find the margin between the final framebuffer becoming ready for a pageflip and the pageflip actually happening?< pq> some kind of fence thing that would give me a timestamp?< danvet> pq, we don't have that readymade< danvet> you could grab a timestamp right before the eglswap with a gl query< danvet> the clocks aren't the same though, so you need to convert yourself and correct for different baseline&drift< danvet> gl has a synchronous query too iirc< danvet> then compare with the timestamp for flips< danvet> once we have generic async atomic in the helpers we could put a tracepoint in there